Container closures are available in a variety of configurations and constructions. One type of closure includes a threaded cap portion that threadedly engages a complementary thread on a container neck. Another type of closure includes a snap-type cap having a locking bead around a portion of the cap depending skirt, that engages a complementary locking portion on a container.
In order to provide visibly discernable evidence of tampering, a number of tamper indicating configurations have come into widespread use. In one type of tampering indicating arrangement, the closure cap includes a tamper evident band that depends from the cap skirt. The band fractures or separates, either fully or partially, from the skirt portion as the cap is removed from the container to provide tamper indication.
Another arrangement includes a sealing liner positioned between the closure and an upper sealing edge of the container neck. The liner is then sealed, such as by heat sealing, to the sealing edge of the container neck. In this manner, access to the inside of the container is possible only by breaking or removing the liner from the container.
In one known liner arrangement, a pull tab is formed as part of the liner. The pull tab can be configured to retain the liner in the closure prior to applying the closure to a container. The tab can also be configured to facilitate removing the liner from the container.
In some known arrangements, the liner contains a plurality, e.g., three, such tabs. The pull tab is a relatively small, integral extension of the liner that extends beyond the periphery of the liner that is sealed to the container neck edge. Such pull tabs are well known in the art.
In order to integrate the pull tab with the closure package, e.g., a closure cap and container, a variety of configurations are known. In one arrangement, the tab is folded over the liner so as to rest within the periphery of the liner, between the liner and the top wall of the cap when the closure cap is placed over the liner, on to the container. In another known configuration, referred to as a tab-down configuration, the pull tab is folded downwardly, onto the container neck, in conjunction with placing the closure on the container. In this manner, the pull tab does not interfere with subsequent sealing of the liner to the container neck. Pull tabs of the tab-down configuration can extend over the container and closure threads.
There are, however, a number of drawbacks to the tab-down arrangement. First, it has been observed that the tabs may tend to push the liner slightly toward the cap thread. As the tab pushes toward the thread, the pressure can cause the liner to protrude inside of the cap, exposing it to potential contact with the container edge, during cap application. This, in turn, can cause incomplete contact between the liner and the container neck edge. It has also been observed that the tab can push inward, toward the center of the liner, again causing incomplete contact between the liner and the container neck edge during cap application. Those skilled in the art will recognize that this incomplete contact can result in failure to effect a complete seal of the container, and thus an unacceptable seal.
Accordingly, there continues to be a need for a container closure liner tab of the tab-down type that maintains the liner in position in the closure prior to applying the closure onto a container. Such a pull tab maintains the positioning of the liner, while minimizing or reducing interference with application of the closure to a container. Further, such a pull tab provides sufficient gripping area for a user to remove the liner from the container upon first use.